1. Field of the Invention
The present invention relates to improvements in portable data devices of the type wherein data may be keyed, viewed for accuracy, recorded on magnetic tape, recalled from magnetic tape, and telephonically transmitted for processing.
2. Description of the Prior Art
At the present time there are various types of data collection systems in use for collecting and recording various types of data. Data that is collected by these systems is usually transmitted by conventional means to a central computer for further processing. These data collection systems are especially useful to supermarkets and drug stores as a means of ordering merchandise.
One type of data collection system developed to date generally uses a modified adding machine as an input device to a recording medium. These types of systems are usually cumbersome to use, since carts are required to transport them. Furthermore, these systems require conventional 110 volt electricity for operation, leading to awkward power cords and limited mobility.
Portable data entry devices have been developed to alleviate some of the problems associated with the above devices. These portable devices have not, however, provided total flexibility. Moreover, they have not provided sufficient safeguards against un-noticed operator error, e.g., inadvertent deletion of data, and they have been too complicated for many users to operate correctly and consistently, especially untrained persons.